With the development of VR (Virtual Reality) technologies, several input and output devices have been created. There is a category of interaction devices that is becoming important due to the increasing availability of digital cameras. This kind of optical device uses the image captured by a set of digital cameras to track the position of objects and to provide positioning and orientation data for RV systems. This paper presents the development of two low-cost optical tracking devices with six degrees of freedom for desktop applications. The first device uses three webcams mounted on a box and detects the movements of a white marker over its black background. An alternative approach is also presented, using a single camera that, when moved by the user over a mark, works as a 3D mouse. Finally, the use of these devices in VR applications is presented.